Lê AD, Wang A, Harding S, Juzytsch W, Shaham Y. Nicotine increases alcohol self-administration and reinstates alcohol seeking in rats.
Psychopharmacology (Berl) 2003;
168:216-221. [PMID:
12536264 DOI:
10.1007/s00213-002-1330-9]
[Citation(s) in RCA: 135] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2002] [Accepted: 10/22/2002] [Indexed: 10/26/2022]
Abstract
RATIONALE AND OBJECTIVE
Alcohol and tobacco are often co-abused in humans and previous studies found that nicotine increases alcohol consumption in rats. Here, we studied whether nicotine would reinstate alcohol-taking behavior in drug-free rats and whether this effect would be enhanced by prior exposure to nicotine during alcohol self-administration training.
METHODS
Rats were trained to press a lever for alcohol (12% w/v, 1 h/day), and following stable alcohol intake groups of rats ( n=11-12) were given daily vehicle or nicotine (0.2, 0.4 or 0.8 mg/kg, SC) injections just prior to the self-administration sessions for 10 days. Rats were then given 6 days of alcohol self-administration in the absence of nicotine and an additional 5-10 drug-free days during which lever presses were not reinforced (extinction). Subsequently, rats were tested for reinstatement of alcohol seeking following exposure to priming injections of vehicle or nicotine (0.4 mg/kg, SC).
RESULTS
Nicotine increased alcohol self-administration in a dose- and time-dependent manner over the 10-day period. Nicotine also reinstated alcohol seeking after extinction of the alcohol-reinforced behavior, and this effect was strongly enhanced by prior nicotine exposure.
CONCLUSIONS
The present data extend previous studies on the effect of nicotine on alcohol self-administration, and further indicate that nicotine is an effective stimulus for reinstatement of alcohol seeking during drug-free periods.
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